This Apache module, with the netsnmp plugin enables you to live monitoring your Webserver allowing to monitor the entire server, and if you want each of your VHosts or (Wild)Aliases.
Is able to monitor and signalate via TRAP reconfiguration or entire server shutdown/crash.
Using Atomical operations and MMAP server overhead is minimal.
Contrib from Alf Høgemark for integrating it in OpenNMS: http://www.kanonbra.com/index.php/projects/performance-testing/24-monitoring-apache-http-server...